The present invention relates to fastening systems for belting, and in particular to a sheath for lacing hooks, and the like.
Endless belts are used extensively in a wide variety of different commercial and industrial applications, such as conveyor belts and power drive belts in agricultural equipment, airport baggage conveyor systems, mining conveyors, and many other similar systems. The ends of such endless belts are typically interconnected by a lacing, which is usually flexible to permit the belt to pass over pulleys. One common type of lacing comprises a plurality of wire hooks that have sharpened points on opposite legs clenched or embedded in the leading and trailing ends of the belt. The loop ends of the hooks are meshed together, and a pin extends through the meshed loops to interconnect the opposite ends of the belt.
One type of wire hook lacing employs "carded hooks," which comprise separate hooks that are individually mounted on a piece of cardboard or a card of similar material to retain the same in their proper spacing and orientation for insertion into a crimping machine. Examples of such carded hooks are disclosed in U.S. Pat. Nos. 1,393,451 and 1,894,981. Once the carded hooks are set in place in the crimping machine, the card is removed, and a jaw portion of the crimping machine then retains the hooks in place as they are crimped onto one end of the belt.
Another type of wire hook lacing employs "bar hooks," or "welded bar hooks," which comprise a plurality of hooks that are rigidly interconnected in a side-by-side relationship to form a strip of hooks. The rigid interconnection of the hooks both facilitates insertion of the hooks into a crimping machine, and also reinforces the finished lacing. Examples of such bar hooks are disclosed in U.S. Pat. Nos. 1,498,275 and 1,768,935. In one type of bar hook, a rigid wire or bar extends laterally across the hooks, and is welded to a leg of each hook at the point of intersection.
The sharpened points of lacing hooks are normally exposed, such that the strips of hooks often become tangled during transport and/or use, which requires rather tedious and time consuming untangling. Also, due to the exposed points on unguarded lacing hooks, the hooks must be handled very carefully to avoid injury.
One prior device used to guard the points of bar hooks is disclosed in an associated "Disclosure Statement," and comprises a rigid, extruded plastic strip having an H-shaped end elevational configuration. This rigid, H-shaped guard strip is slid laterally across the bar hooks, with the outermost hook points positioned within oppositely facing spaces between the upper and lower flanges of the guard strip.
The rigid, H-shaped guard strip discussed above is relatively expensive to manufacture, and is simply discarded after the lacing is completed. Also, the rigid, H-shaped guard strip must be slid laterally off of the bar hooks to be removed therefrom prior to crimping. This type of removal action presents a problem where side clearance is limited, which is particularly prevalent when a belt is laced in place, since conveyor guides, side panels, et cetera, create a lateral obstruction.
Another drawback associated with the use of such rigid, H-shaped guards is that when the bar-hooks are cut to length, the guard must be either removed or repositioned before the strip of bar hooks can be severed, thereby exposing at least some of the hook points.
Yet another disadvantage associated with the H-shaped type of guard strip is that because they are rigid, and the spaces between the upper and lower flanges are relatively wide to insure proper insertion onto the bar hooks points, the guards have a tendency to slide laterally along the length of the bar hook during transport and/or use. This lateral motion causes longitudinal misalignment between the bar hooks and the guard that can expose some of the outermost hooks.